Cervical spinal dural fistulas leading to remote thoracolumbar myelopathy

Purpose of reviewSpinal dural arteriovenous fistulas (SDAVFs) are abnormal connections between 1 or more radiculomeningeal arteries and a single radiculomedullary vein draining into the perimedullary venous system. SDAVFs present in older patients with a progressive myelopathy caused by diffuse spinal venous hypertension. The discrepancy between the focal nature of the arteriovenous shunt and the extent of the induced myelopathy is a classic feature of SDAVFs related to the coexistence of diffuse spinal venous drainage impairment.Recent findingsWe describe 3 cases of cervical SDAVFs (at C1, C4, and C7) presenting with a myelopathy that spared the cervical spinal cord and, in 2 instances, the upper thoracic cord. This is to our knowledge the first observations of cervical SDAVFs with MRI showing absent or subtle flow voids and presenting remote thoracolumbar myelopathy without cervical cord involvement.SummaryA considerable distance may separate low-flow spinal arteriovenous fistulas from the spinal cord damage they produce. These observations emphasize the importance of performing a complete spinal angiogram when investigating a vascular myelopathy of any location and extent.

Evaluation of idiopathic transverse myelitis revealing specific myelopathy diagnoses

ObjectiveTo evaluate specific myelopathy diagnoses made in patients with suspected idiopathic transverse myelitis (ITM).MethodsA total of 226 patients 18 years and older were referred to Mayo Clinic Neurology for suspected ITM from December 1, 2010, to December 31, 2015. Electronic medical records were reviewed for detailed clinical presentation and course, laboratory and electrophysiologic investigations, and neuroimaging to determine the etiology. Current diagnostic criteria for ITM and alternative myelopathy diagnoses were applied. All cases where any discrepancy was suspected from the final reported clinical diagnosis were reviewed by each author and a consensus final diagnosis was made.ResultsThe diagnostic criteria for ITM were met in 41 of 226 patients (18.1%). In 158 patients (69.9%), an alternative specific myelopathy diagnosis was made: multiple sclerosis or clinically isolated syndrome, 75; vascular myelopathy, 41; neurosarcoidosis, 12; neuromyelitis optica spectrum disorder, 12; myelin oligodendrocyte glycoprotein myelopathy, 5; neoplastic, 4; compressive, 3; nutritional, 3; infectious, 2; and other, 2. A myelopathy was not confirmed in 27 patients. Time from symptom onset to final clinical diagnosis in patients without ITM was a median of 9 months (range 0–288). Fifty-five patients (24%) required treatment changes according to their final clinical diagnosis.ConclusionsThe majority of patients with suspected ITM have an alternative specific myelopathy diagnosis. A presumptive diagnosis of ITM can lead to premature diagnostic conclusions affecting patient treatment.

Myelopathy due to intracranial dural arteriovenous fistula: a potential diagnostic pitfall

Intracranial dural arteriovenous fistula (DAVF) is rare and potentially life-threatening disease often presenting as vascular myelopathy. The early and proper diagnosis is challenging because the clinical manifestations are related to the distribution of the draining vein, not the fistula site, and imaging findings are similar to demyelinating disease of the spinal cord. The authors present the case of a 45-year-old man who developed acute progressive quadriplegia and respiratory difficulty with an enhancing, longitudinally extensive cervical cord lesion. These symptoms were highly suspicious for transverse myelitis but were caused by an intracranial DAVF. Intracranial DAVF with venous reflux to the brainstem and spinal cord is a rare but important differential diagnosis of progressive worsening myelopathy that is treatment resistant and gives the diagnostic impression of transverse myelitis.

Spinal Arteriovenous Epidural Fistula with Acute Paraplegia

We report a case of a 68-year-old woman with an acute paraplegia due to venous congestion of the spinal cord caused by an exclusive epidural arteriovenous fistula. Diagnosed by MRI and selective spinal angiography the fistula was embolized during emergency treatment via transarterial access. Immediately after the intervention the paraplegia declined and the patient recovered completely. Epidural AV fistulae are a very rare and therefore relatively unknown cause of vascular myelopathy. They may require emergency management to avoid permanent neurological deficits.